Appendix C. Probes 149be granted read access to your log files.Note that data from the first run of these probes will not be measured against the thresholds to preventspurious notifications caused by incomplete metric data. Measurements will begin on the second run.C.6.1. LogAgent::Log Pattern MatchThe LogAgent::Log Pattern Match probe uses regular expressions to match text located within the logfile being monitored and collects the following metrics:• Regular Expression Matches — The number of matches that have occurred since the probe last ran.• Regular Expression Match Rate — The number of matches per minute since the probe last ran.Requirements — The Red Hat Network Monitoring Daemon (rhnmd) must be running on the moni-tored system to execute this probe. For this probe to run, the nocpulse user must be granted readaccess to your log files.In addition to the name and location of the log file to be monitored, you must provide a regularexpression to be matched against in regex format for egrep, which is equivalent to grep -E insupport for extended regular expressions. This is the regex set for egrep:^ beginning of line$ end of line. match one char* match zero or more chars[] match one character set, e.g. ’[Ff]oo’[^] match not in set ’[^A-F]oo’+ match one or more of preceding chars? match zero or one of preceding chars| or, e.g. a|b() groups chars, e.g., (foo|bar) or (foo)+WarningDo not include single quotation marks (’) within the expression. Doing so will cause egrep to failsilently and the probe to time out.Field ValueLog file* /var/log/messagesBasic regular expression*Timeout* 45Critical Maximum MatchesWarning Maximum MatchesWarning Minimum MatchesCritical Minimum MatchesCritical Maximum Match RateWarning Maximum Match Rate
